Hey there,
I have a block with a 9390010 and I pulled the pan and noticed that it is a 4bolt main. I have a crank with 9392442 and pistons TWR 4.0.3.0 and 6.0inch connecting rods. Would this combination create a 383? Thanks

Hey there,
I have a block with a 9390010 and I pulled the pan and noticed that it is a 4bolt main. I have a crank with 9392442 and pistons TWR 4.0.3.0 and 6.0inch connecting rods. Would this combination create a 383? Thanks

No. The crank and bore size dictate the displacement. In your case, the stroke is 3.48" and the bore size is 4.030". That make a 355. They must be older pistons if they have anything that says TRW on them. How are you determining the length of the rods?

Sorry Tom, I tried to figure out how to move the question to engines. I meseaured from the middle where the Connecting rod is spaced around the crank to the bas of the interior piston where it connects. I measured 6.0 and I was wondering if they could be tring to Deck the block and gain the strock with 6.0 rods. is that possible? Also if this is a 355 is this worth builing?

Would it be worth investing money into this build or should I go another way. I am building a 74 nova and would like to run low 12s high 11s. I have a set of Brodix aluminum heads 64cc 202/160 that I was going to use. the pistons are .05 D dished

rod length won't change displacement, only bore and stroke. Rod lengths are center-to-center. Measure from the middle of the crank bore to the middle of the pin bore on the rod. If the pins are still installed, measure to the bottom of the pin and add half the pin diameter (.921" on an SBC? I forget)

I remeasured and it looks like I measured correctly the first time but discribed it incorrectly. I still get a 6.0 rod. Also I thought that if a piston was marked as 4.0.3.0 isnt that a 350 bored 30 over? I just want to make sure that I have a 355 now and not a 383...which is what I paid for...Also what type of cam shoudl I run I have a th350/2400 tourqe converter and 373 posi rear end

A 442 crank is a 3.48" stroke crankshaft, I believe. Your pistons are 4.030" in size giving you 355 ci. Like the guys mentioned, rod size doesn't determine ci size. Some 383 engine use 5.565" rods, but that's normally using a stock 400 crank turned to the size of a 350's mains, which is the old school way of doing things.

I agree. Sounds like a 355. Are the heads off with a piston still in it? If so, pretty easy to measure stroke. If its 3-1/2" its a 355. If its 3-3/4" its a 383. If the pistons are out with the crank still in, you can still do it. Just put the rod bearing as far away from the deck as it goes and measure up to the deck. Do the same at TDC and subtract.

Sounds like you measured the rods correctly. Another clue would be the ring pack. A 6" rod with a 383 is easily done, but it puts the pin into the rings. If the pin bore is below all three rings, its almost certainly a 3.48" stroke. If the oil ring groove goes through the top of the pin bore, chances are its a 3.75" stroke. That's not always fact, but its true 93.833493285% of the time.

ok so my fears have been anwsered. I have a 355! with Ibeam 6.0 rods. I have no clue what the guy was thinking when he built the engine. Could anyone help me out? Should I just trash this engine build?

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